| From: | John Beaver <john(dot)e(dot)beaver(at)gmail(dot)com> |
|---|---|
| To: | Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> |
| Cc: | Jeremy Harris <jgh(at)wizmail(dot)org>, Pgsql-Performance <pgsql-performance(at)postgresql(dot)org> |
| Subject: | Re: sequence scan problem |
| Date: | 2008-07-01 00:37:58 |
| Message-ID: | 48697C66.5040501@gmail.com |
| Views: | Raw Message | Whole Thread | Download mbox | Resend email |
| Thread: | |
| Lists: | pgsql-performance |
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<meta content="text/html;charset=ISO-8859-1" http-equiv="Content-Type">
</head>
<body bgcolor="#ffffff" text="#000000">
<chuckle> You're right - for some reason I was looking at the (18
rows) at the bottom. Pilot error indeed - I'll have to figure out
what's going on with my data.<br>
<br>
Thanks!<br>
<br>
Tom Lane wrote:
<blockquote cite="mid:28999(dot)1214839555(at)sss(dot)pgh(dot)pa(dot)us" type="cite">
<pre wrap="">John Beaver <a class="moz-txt-link-rfc2396E" href="mailto:john(dot)e(dot)beaver(at)gmail(dot)com"><john(dot)e(dot)beaver(at)gmail(dot)com></a> writes:
</pre>
<blockquote type="cite">
<pre wrap="">Ok, here's the explain analyze result. Again, this is Postgres 8.3.3 and
I vacuumed-analyzed both tables directly after they were created.
</pre>
</blockquote>
<pre wrap=""><!---->
</pre>
<blockquote type="cite">
<pre wrap=""> Merge Join (cost=1399203593.41..6702491234.74 rows=352770803726
width=22) (actual time=6370194.467..22991303.434 rows=15610535128 loops=1)
</pre>
</blockquote>
<pre wrap=""><!----> ^^^^^^^^^^^
Weren't you saying that only 50 rows should be returned? I'm thinking
the real problem here is pilot error: you missed out a needed join
condition or something. SQL will happily execute underconstrained
queries ...
regards, tom lane
</pre>
</blockquote>
</body>
</html>
| Attachment | Content-Type | Size |
|---|---|---|
| unknown_filename | text/html | 1.4 KB |
| From | Date | Subject | |
|---|---|---|---|
| Next Message | Emiliano Leporati | 2008-07-01 10:49:19 | un-understood index performance behaviour |
| Previous Message | Mark Roberts | 2008-06-30 20:24:54 | Re: Does max size of varchar influence index size |